Before starting to record fiff file, send "info" command to achieve the latest gain.
Update fiff info; add one icons/down.png
change name of icons
add the adjustable data length for spectrum calculation
dbg: matching pursuit toolbox
Merge pull request #132 from liminsun/master

Before starting to record fiff file, send "info" command to achieve the ...
Merge branch 'master' of https://github.com/mne-tools/mne-cpp
Merge branch 'master' of https://github.com/LostSign/mne-cpp
fix: save_fif_file